Hull and deck released from the mould for Edmond de Rothschild
Set in motion last September, the construction of the future Imoca monohull Edmond de Rothschild is continuing to progress at the Multiplast yard in Vannes, south-west Brittany. Week on week, the pieces of the giant puzzle are coming together. Indeed, two of the boat's main sections, the hull and the deck, were successfully released from their mould this week. These operations, which have taken up nearly 12,500 man-hours with a team of some twenty or so people, marks the end of the first phase devoted to the tooling, lay-up and other cooking processes and opens the way to the second so-called assembly phase. With four months until the scheduled June launch, the carbon outline is taking shape, exposing the assertive lines of the latest generation monohull.
A fine work
The atmosphere has been coloured by a series of major operations this week in the western hangar of the Vannes-based yard. Indeed, on Tuesday morning, the deck of Gitana 16 left its mould and was suspended mid-air a few metres away. The following day, it was the turn of the hull to follow suit. Though these operations to release the structures from the mould are but a formality for the yard, it is no less formal a ceremony. It was with a mixture of excitement and stress then that the project's various protagonists got to see the outline' of the most recent Verdier design.
The release from the mould is naturally a key stage in the construction of the boat, as it's the first time you really get to see her form. It is only then that you get to see the piece as a whole and see the appearance of the hull's surface, which is an important indication of the build quality. These moments in the life of the project are a bit stressful, but also very enjoyable, as they bring a sense of closure with regards the numerous questions running around your mind. We're always keen to see the surface condition, to know if the mould has marked the piece, to be able to check for defects and consequently if everything is compliant with the architect's plans. Today that is the case, so it's a very good day! explains Pierre Tissier, Gitana Team's technical director responsible for monitoring the build. The required quality checks were carried out during the manufacture of the pieces prior to their release from the mould. In fact, such checks have been made at every stage of construction: after the 1st skin was laid, during gluing of the honeycomb to check its bonding and finally the inner skin. As such the elements are deemed to be sound.
After an initial inspection of the two large carbon sections, a look of satisfaction was evident on the faces of members of both the Gitana Team and the Multiplast team, which have worked relentlessly over the past six months so as to adhere to the specifications and the build schedule.
The Vendée Globe project is a global challenge. Naturally it's a sporting and human challenge, but it's also a technological gamble. The architectural choices are crucial, but the implementation of the latter is equally important. We really need to pay tribute to the quality of the work carried out by Yann Penfornis' teams. The close collaboration which exists between Gitana's design office, through Pierre Tissier, who is in charge of on-site monitoring, and the Multiplast yard, is bearing fruit, General Manager of Gitana Team, Cyril Dardashti was keen to stress.
A new generation' look
The pieces are not yet assembled of course but with a small amount of imagination you can already picture the future 60' Edmond de Rothschild. The third monohull of the latest generation created by the Verdier VPLP consortium, in close collaboration with Gitana Team's design office, the boat boasts a sleek style. Featuring a planing hull equipped with a high volume bow to enhance the boats performance, a tumblehome hull so as to limit the beam of the deck and thus make her more lightweight, reduction of the freeboard, which further accentuates the boat's beaminess, flat deck, open cockpit, not to mention foils instead of the old generation conventional daggerboards Gitana 16 certainly doesn't lack character.
Assembly during April
The technical director of the five-arrow' team gives us a broad outline of the upcoming phases: The coming weeks will be devoted to the installation of the hull and deck bulkheads. Once the structures have been bonded we'll be able to close the lid on the assembly proper of the hull and deck; a phase which should be complete in April. This phase promises to quite unique and it will be a first for the teams as Gitana 16 is split horizontally in the middle of the freeboard along her entire length. Usually, we complete the deck/hull (hull as far as the sheerline) assemblies, whilst in this instance half the hull is in the deck. Without going into too much detail, that's linked to the hull below the waterline, concludes Pierre Tissier.
With a scheduled launch for June 2015, there are still four months of intense work ahead before Sébastien Josse and Gitana Team can finally get a taste of what this new craft is like to sail. With the removal of these pieces from the mould the project suddenly seems more real. For months now, in collaboration with the architects and Gitana's design office, we've been going into the little details of this boat and all the resulting systems. Now though, I can really begin to cast my mind forward to the first sea trials this summer and in the longer term, even though it's not just around the corner, thoughts about the round the world that awaits me with this monohull! I'm really keen to see this boat hit the water, put in the first tacks and above all soak up the initial sensations, admitted the skipper of Gitana Team.
Honeycomb: In the marine industry, the core of a sandwich panel is often a honeycomb structure. This honeycomb structure is comprised of Nomex' in this instance, with a special variety of cardboard'.
Sandwich: To design stiff panels, a technique currently used in the composite material industry is that of sandwich structures, which consist of two carbon skins bonded to a thick but light core like foam or honeycomb. This assembly enables the creation of stiff, light panels, though they have a poor resistance to repeated impact over time. As such, this technology is only used for the hull's aft section.
A tumblehome hull: A hull is described as having tumblehome when the maximum beam of the hull is greater than the beam at deck level.
Sheerline: A line formed by the intersection of the hull and deck.
Hard chine: A hard edge on the hull that is intended, by deflecting the flow of water, to reduce the boat's dynamic wetted surface and hence the resistance when making headway.
Freeboard: Vertical distance between the waterline and the sheerline.
Bulkheads: The main transverse elements of the boat structure, the bulkheads are structural elements bonded to the deck and the hull, which enhance the boat's stiffness.